Leaf sampling. In commercial winter and spring
wheat fields at different places of Lithuania, 30–50 flag
leaves of wheat were collected at GS 73–75 growth
stages. Every year the number of visited sites varied
from 18 to 20; however, not in all sites disease symptoms
were present. Locations, where wheat leaf samples with
Mycosphaerella graminicola symptoms were collected
are presented in Table 1. Each site was approximately
50–80 km apart from one another. Leaf samples were
dried and frozen until the start of the experiment.